scholarly journals Estimation of chlorophyll concentration in maize using spectral reflectance

2015 ◽  
Vol XL-7/W3 ◽  
pp. 65-71 ◽  
Author(s):  
L. J. Martinez ◽  
A. Ramos
Keyword(s):  
Chlorophyll Content ◽  
Chlorophyll Concentration ◽  
Spectral Indices ◽  
Strong Correlations ◽  
Spectral Measurements ◽  
Maize Crop ◽  
Chlorophyll Contents ◽  
N Rates ◽  
Reflectance Indices ◽  
The Relationship

The objective of this research was to identify the relationship between chlorophyll contents and spectral measurements in a maize crop. Spectral measurements were taken and the chlorophyll content was determined in leaf samples in a field experiment with different N rates. Analysis of variance showed differences in the chlorophyll content and spectral indices for the treatments and strong correlations between some reflectance indices and chlorophyll content. Due to a relationship between the N and chlorophyll contents, the results proved to be important for making decisions related to the nitrogen supply for crops, which is crucial in agriculture.

scholarly journals Chlorophyll as an indicator of green tea quality

2014 ◽  
Vol 83 (10) ◽  
pp. S103-S109 ◽  
Author(s):  
Martina Ošťádalová ◽  
Bohuslava Tremlová ◽  
Jana Pokorná ◽  
Martin Král
Keyword(s):  
Chlorophyll Content ◽  
Green Tea ◽  
Storage Time ◽  
Chlorophyll Concentration ◽  
Storage Period ◽  
Storage Conditions ◽  
Qualitative Variable ◽  
Chlorophyll Contents ◽  
Tea Quality ◽  
The Relationship

The objective of this work was to study the changes in chlorophyll contents in green teas stored under different conditions and to suggest the most suitable way and length of green tea storage. A secondary aim was to evaluate the possibility of using the chlorophyll content as an indicator of tea freshness. Samples for analysis were obtained from a range of tea-growing regions. Chlorophyll contents were measured using UV-vis spectrophotometry. Chlorophyll absorbance was measured at 642.5 and 660 nm. Prior to storage, chlorophyll concentration in teas ranged from 1.12 to 1.89 mg per 1 g of tea, which corresponded to data given by other authors. Storage was found to lead to a decline in chlorophyll concentration. From the 6th month of storage onwards, a significant decrease (P < 0.05) was observed in all samples, irrespective of storage conditions. Based on the findings of this study, original and metal packaging can be considered the most chlorophyll-friendly. On the other hand, glass and paper packaging stored in direct daylight were found to have the strongest impact on chlorophyll concentration. Overall, it can be concluded that the storage time can have a strong influence on oolong green tea colour as an important qualitative variable. Thus, the shelf-life of tea should be shorter than the 12 months claimed by most manufacturers. Once the relationship between changes in chlorophyll concentration and length of the storage period had been established, the chlorophyll content was suggested as an indicator of the storage time (freshness) of a tea substance.

scholarly journals Nutrients Assimilation and Chlorophyll Contents for Different Grapevine Varieties in Calcareous Soils in the Somontano DO (Spain)

Beverages ◽  
2018 ◽  
Vol 4 (4) ◽  
pp. 90 ◽  
Author(s):  
José Casanova-Gascón ◽  
Pablo Martín-Ramos ◽  
Clara Martí-Dalmau ◽  
David Badía-Villas
Keyword(s):  
Chlorophyll Content ◽  
Fruit Set ◽  
Chlorophyll Concentration ◽  
Calcareous Soils ◽  
Pinot Noir ◽  
Growth And Yield ◽  
Cabernet Sauvignon ◽  
Chlorophyll Contents ◽  
Young Leaves ◽  
The Impact

Lime-induced chlorosis (LIC) is an important abiotic constraint affecting the growth and yield of grapevines growing in calcareous soils in the Mediterranean region, and the sensory properties of the produced wine. In the work presented herein, the impact of LIC on the nutritional status and chlorophyll content was assessed for eleven varieties and a clone (Merlot, Pinot Noir, Cabernet Sauvignon, Tempranillo, Parraleta, Moristel, Aglianico, Macabeo, Sauvignon, Chardonnay, and Riesling), grafted to the same rootstock (1103 Paulsen). Macro- and micronutrient contents were determined in the fruit set and veraison stages by petiole analyses, while chlorophyll content in young leaves was monitored by SPAD. Significant differences were detected amongst varieties for all nutrients (including Fe), and inverse relationships between Fe and P contents in the petiole and chlorophyll concentration in the young leaves were found. Regarding LIC resistance, the Fe and chlorophyll contents suggest that Cabernet Sauvignon, Tempranillo and Aglianico varieties would show the best performance, while Sauvignon would be the least tolerant.

Using PROSEPCT and SVM for the Estimation of Chlorophyll Concentration

2014 ◽  
Vol 989-994 ◽  
pp. 2184-2187
Author(s):  
Jie Lv ◽  
Feng Li Deng ◽  
Zhen Guo Yan
Keyword(s):  
Chlorophyll Content ◽  
Large Scale ◽  
Chlorophyll Concentration ◽  
Support Vector ◽  
Maximum Correlation ◽  
Dynamic Prediction ◽  
West Lake ◽  
Chlorophyll Contents ◽  
Irrigated Area ◽  
Vector Machines

This study focused on estimating chlorophyll concentration of rice using PROSPECT and support vector machine. The study site is located in West Lake sewage irrigation area of Changchun, Jiliin Province. Reflectance spectrual of rice were measured by ASD3 spectrometer, chlorophyll contents of rice were recorded with a portable chlorophyll meter SPAD-502. Support vector machines and PROSPECT model were adopted to construct hyperspectral models for predicting chlorophyll content. The results indicate that: the hyperspectral prediction model of rice chlorophyll content yields a maximum correlation coefficient of 0.8563, and achieves a smallest RMSE of 9.5106; and the prediction accuracy based on the first derivative spectrum is higher than on the original spectrum. Research of this paper provides a theoretical basis for large scale dynamic prediction of rice chlorophyll content in sewage irrigated area.

THE RELATIONSHIP BETWEEN CHLOROPHYLL CONTENT AND RATE OF PHOTOSYNTHESIS IN SOYBEANS

1977 ◽  
Vol 57 (1) ◽  
pp. 1-5 ◽  
Author(s):  
B. R. BUTTERY ◽  
R. I. BUZZELL
Keyword(s):  
Linear Regression ◽  
Chlorophyll Content ◽  
Photosynthetic Rate ◽  
Regression Line ◽  
Quadratic Equation ◽  
Chlorophyll Contents ◽  
Rate Of Photosynthesis ◽  
Highly Correlated ◽  
The Relationship ◽  
Selection Of

Photosynthetic rate of soybeans (on a leaf area basis, PA) estimated from the incorporation of 14CO2 under field conditions was highly correlated with chlorophyll content of the side leaflets of the same leaves. Among a collection of 48 cultivars, the linear regression of PA on chlorophyll content accounted for 44% of the variation, whereas with a selection of genotypes with various mutant chlorophyll genes, the regression accounted for 81%. When the data for the two tests were re-calculated relative to the check cv. Altona, a quadratic equation between PA and chlorophyll accounted for nearly 90% of the variation. When photosynthetic rate was expressed on a unit chlorophyll basis (Pc), no significant differences among lines were established in the cultivar test. In the mutants test, significant differences in Pc were established with higher values of Pc associated with lower chlorophyll contents; a linear regression accounted for 45% of the variation. Transformation of the data from both experiments relative to Altona allowed the fitting of a common regression line (quadratic) which accounted for 63% of the variation. We suggest that initial screening of progenies in a breeding program for high photosynthetic rate could be done by measuring chlorophyll content.

CONTROL OF CHLOROPHYLL CONTENT BY DAYLENGTH IN LEAVES OF MARQUIS WHEAT

1961 ◽  
Vol 39 (1) ◽  
pp. 51-63 ◽  
Author(s):  
D. J. C. Friend
Keyword(s):  
Chlorophyll Content ◽  
Chlorophyll Concentration ◽  
Leaf Thickness ◽  
Floral Initiation ◽  
Fresh Weight ◽  
Fresh Weight Basis ◽  
Chlorophyll Contents ◽  
Mature Leaves ◽  
Unit Leaf ◽  
Stage Of Development

The maximal chlorophyll contents reached during the growth of each of the first three leaves of Marquis wheat increased linearly with daylength, when the plants were grown from germination under illumination of 1750 ft-c intensity for daily periods of 8, 16, or 24 hours. This effect of daylength was also seen when chlorophyll concentration was expressed on a unit leaf area or fresh weight basis, and was related to increased leaf thickness at the longer daylengths. The increased chlorophyll content and concentration under long daylengths could not be duplicated by extending short daylengths with low-intensity supplementary light. Previous experiments suggest that the control of chlorophyll content by daylength is through the control of leaf thickness by the total amount of daily energy.The ratio of chlorophyll a to b in mature leaves did not vary with daylength. There was also no change in the maximal chlorophyll concentration of leaves mature at the time of floral initiation compared with those mature in the vegetative stage of development.

scholarly journals Assessing Wildfire Burn Severity and Its Relationship with Environmental Factors: A Case Study in Interior Alaska Boreal Forest

2021 ◽  
Vol 13 (10) ◽  
pp. 1966
Author(s):  
Christopher W Smith ◽  
Santosh K Panda ◽  
Uma S Bhatt ◽  
Franz J Meyer ◽  
Anushree Badola ◽  
...  
Keyword(s):  
Boreal Forest ◽  
Ground Truth ◽  
Burn Severity ◽  
Classification Methods ◽  
Spectral Indices ◽  
Ground Truth Data ◽  
Burn Scar ◽  
Interior Alaska ◽  
Remote Sensing Methods ◽  
The Relationship

In recent years, there have been rapid improvements in both remote sensing methods and satellite image availability that have the potential to massively improve burn severity assessments of the Alaskan boreal forest. In this study, we utilized recent pre- and post-fire Sentinel-2 satellite imagery of the 2019 Nugget Creek and Shovel Creek burn scars located in Interior Alaska to both assess burn severity across the burn scars and test the effectiveness of several remote sensing methods for generating accurate map products: Normalized Difference Vegetation Index (NDVI), Normalized Burn Ratio (NBR), and Random Forest (RF) and Support Vector Machine (SVM) supervised classification. We used 52 Composite Burn Index (CBI) plots from the Shovel Creek burn scar and 28 from the Nugget Creek burn scar for training classifiers and product validation. For the Shovel Creek burn scar, the RF and SVM machine learning (ML) classification methods outperformed the traditional spectral indices that use linear regression to separate burn severity classes (RF and SVM accuracy, 83.33%, versus NBR accuracy, 73.08%). However, for the Nugget Creek burn scar, the NDVI product (accuracy: 96%) outperformed the other indices and ML classifiers. In this study, we demonstrated that when sufficient ground truth data is available, the ML classifiers can be very effective for reliable mapping of burn severity in the Alaskan boreal forest. Since the performance of ML classifiers are dependent on the quantity of ground truth data, when sufficient ground truth data is available, the ML classification methods would be better at assessing burn severity, whereas with limited ground truth data the traditional spectral indices would be better suited. We also looked at the relationship between burn severity, fuel type, and topography (aspect and slope) and found that the relationship is site-dependent.

scholarly journals Effects of 1-MCP on External Postharvest Qualities and Shelf Life of ‘Maha Chanok’ Mango Fruit

2015 ◽  
Vol 8 (1) ◽  
pp. 68
Author(s):  
B. Chutichudet ◽  
Prasit Chutichudet ◽  
Usana Trainoak
Keyword(s):  
Chlorophyll Content ◽  
Fruit Weight ◽  
Storage Life ◽  
Fruit Firmness ◽  
Mango Fruit ◽  
Chlorophyll Contents ◽  
Randomized Design ◽  
Fruit Decay ◽  
Completely Randomized Design ◽  
And Storage

<p>‘Maha Chanok’<strong> </strong>mango is an economic fruit crop widely cultivated commercially throughout Thailand. By nature, mango fruit has a rather limited storage life after harvest. 1-methylcyclopropene (1-MCP) has been accepted as a commercial substance to improve several fruit qualities. The objective of this research was to study the effects of 1-MCP on the external postharvest qualities and storage life on the ‘Maha Chanok’ mango fruit. The experiment was laid out in a Completely Randomized Design with three replicates, ten fruits per replicate. Mango fruit was fumigated with 1-MCP at three concentrations (1000, 1250, or 1500 nl l<sup>-1</sup>) and three fumigation periods (12, 18, or 24 h), compared with the control fruit. After treating, all treatments were stored under ambient temperature (27 °C, 80%R.H.). The following determinations were made every two days for assessment of fruit weight loss, firmness, chlorophyll content, decay incidence, and storage life. The results showed that fruit treated with 1500 nl l<sup>-1</sup><strong> </strong>1-MCP for 24 h had the maximal fruit firmness. For chlorophyll content, the results showed that fruit-treated with 1500 nl l<sup>-1</sup><strong> </strong>1-MCP for 12 h could effectively retain the highest chlorophyll contents. Furthermore, both the lowest fruit decay and the longest storage life of 12 days were achieved from the fruit treated with 1000 nl l<sup>-1</sup><strong> </strong>1-MCP for 12 h.</p>

scholarly journals Similarity Search and Correlation-Based Exploratory Analysis in EHRs: A Case Study with COVID-19 Databases

2021 ◽  
Author(s):  
Mirela T. Cazzolato ◽  
Lucas S. Rodrigues ◽  
Marcela X. Ribeiro ◽  
Marco A. Gutierrez ◽  
Caetano Traina Jr. ◽  
...  
Keyword(s):  
Data Analysis ◽  
Similarity Search ◽  
Search Task ◽  
Exploratory Analysis ◽  
Strong Correlations ◽  
Health Records ◽  
Categorical Information ◽  
Exploratory Data ◽  
The Relationship

With the COVID-19 pandemic, many hospitals have collected Electronic Health Records (EHRs) from patients and shared them publicly. EHRs include heterogeneous attribute types, such as image exams, numerical, textual, and categorical information. Simply posing similarity queries over EHRs can underestimate the semantics and potential information of particular attributes and thus would be best supported by exploratory data analysis methods. Thus, we propose the Sketch method for comparing EHRs by similarity to provide a tool for a correlation-based exploratory analysis over different attributes. Sketch computes the overall data correlation considering the distance space of every attribute. Further, it employs both ANOVA and association rules with lift correlations to study the relationship between variables, allowing a deep data analysis. As a case study, we employed two open databases of COVID-19 cases, showing that specialists can benefit from the inference modules of Sketch to analyze EHRs. Sketch found strong correlations among tuples and attributes, with statistically significant results. The exploratory analysis has shown to complement the similarity search task, identifying and evaluating patterns discovered from heterogeneous attributes.

scholarly journals The relationship between SPAD chlorophyll and disease severity index in Ganoderma-infected oil palm seedlings

2019 ◽  
Vol 17 (3) ◽  
pp. 355-358 ◽  
Author(s):  
M.R.M. Rakib ◽  
A.H. Borhan ◽  
A.N. Jawahir
Keyword(s):  
Chlorophyll Content ◽  
Disease Severity ◽  
Oil Palm ◽  
Single Photon ◽  
Linear Trend ◽  
Severity Index ◽  
Quadratic Model ◽  
Wood Block ◽  
Disease Severity Index ◽  
The Relationship

Establishment of disease in oil palm seedlings through artificial inoculation of Ganoderma are widely used for studies of various aspects of plant pathology, including epidemiology, etiology, disease resistance, host-parasite interaction and disease control. The estimation of chlorophyll content in the infected seedlings possibly could provide a good indicator for degree of disease or infection, and changes during pathogenesis. Thus, the objective of this study was to evaluate the relationship between disease severity index (DSI) and chlorophyll content in Ganoderma infected oil palm seedlings. Three-month-old oil palm seedlings were infected with Ganoderma inoculum on rubber wood block (RWB), where 44 isolates of Ganoderma were tested. Disease severity index (DSI) and chlorophyll content using a single-photon avalanche diode (SPAD) meter were recorded at 4 weeks interval for a period of 24 weeks after inoculation (WAI). Pearson's correlation analysis and regression analysis were performed to evaluate the relationship between the variables. It was found that the relationship between DSI and SPAD chlorophyll value was inversely proportional (R = -0.92) in a linear trend (R2 = 0.85). Furthermore, the increasing trend of the DSI across the weeks were fitted in a quadratic model (R2 = 0.99). In contrast, the SPAD chlorophyll value declined in a linear trend (R2 = 0.98). The SPAD chlorophyll value could be considered as a better alternative over the DSI as the SPAD chlorophyll value was strongly related to DSI, as well as able to detect physiological changes in the infected oil palm seedlings at the early stages of pathogenesis. J Bangladesh Agril Univ 17(3): 355–358, 2019

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